Development of genetic sex markers of zig-zag eel (Mastacembelus armatus) by a NGS method

Identifying sex-specific marker with universal applicability is important for the study of unisexual reproduction and sex determination mechanism. In this study, two genetic sex markers of zig-zag eel were identified using a NGS method. Twelve potential male-specific sequences were first obtained by whole genome re-sequencing analysis of three males and three females. After PCR amplification and agarose gel electrophoresis for validation, two male-specific markers were obtained. Moreover, these markers were further verified in different populations in the Pearl River basin, and the accuracy of M2 markers was 100%. In addition, these markers were used to identify the genetic sex of different periods of embryonic development and hatching of juveniles at different time points in the cultured population, and it was found that male to female switching was common in the cultured population. Besides, we also found some embryos with YY genotype. These universal sex-specific markers will lay a good foundation for understanding of sex determination mechanism and development of all-male breeding of zig-zag eel.